回—直肠吻合猪的排泄规律对内源氨基酸校正的影响

为了探讨猪内源氨基酸的估测方法，本试验研究了饲喂粗纤维含量分别为：２．０％、５．０％和８．０％的３种纯合无氨日粮时，荷术猪每天回肠末端干物质排泄量和排泄物中氨基酸含量的变化规律。结果指出：（１）饲喂不同纯合无氮日粮时，荷术猪各天回肠末端干物质排泄量变异系数（Ｃ．Ｖ％）随日粮粗纤维含量的增加而减小；（２）从各组荷术猪回肠末端干物质排泄量变化规律看，至少需３头试验猪，经预饲３天后，再收集３天食糜才能保     

无氮日粮纤维水平对猪内源氨基酸测值的影响

以醋酸纤维素为纤维源配制成粗纤维水平分别为２．０％、５．０％、８．０％的３种无氮日粮,采用３头回—直肠吻合猪,分３期试验,通过３×３拉丁方设计研究在等进食量（７５０ｇ／ｄ）条件下日粮的纤维水平对回—直肠吻合猪消化道内源氨基酸测值的影响。结果表明：除缬氨酸、异亮氨酸和胱氨酸外,无氮日粮的粗纤维水平对回肠末端食糜干物质中其他内源氨基酸含量（％）无显著影响（Ｐ＞０．０５）。而对回肠末端内源氨基酸的总排泄量影响显著（Ｐ＜０．０５）或极显著（Ｐ＜０．０１）。相关分析表明,粗纤维水平与各种内源氨基酸的排泄总量之间存在显著（Ｐ＜０．０５）或极显著（Ｐ＜０．０１）的强相关关系,随无氮日粮中粗纤维水平的升高,各种内源氨基酸排泄量呈直线增加。     

回——直肠吻合猪的排泄规律对饲料氨基酸表观消化率测值的影响

大肠中微生物对蛋白质的降解与合成作用是用全收粪法测定饲料氨基酸生物学效价的主要干扰因素。利用回——直肠吻合术。游离大肠,制作专用于评定氨基酸生物学效价的荷术猪(Hostal swine)不仅可以避免大肠中微生物的作用,而且可以简化用瘘管法收集回肠末端排泄物的采样程序,减少误差来源,提高测值可信度。但采用这种方法时,如何取得有代表性的排泄物样品仍是保证测值精确度的关键问题。为此本试验研究了饲喂粗蛋白质量分别为9.6％、13.5％、17.0％和20.6％的四种半纯合日粮时,荷术猪每天的回肠末端干物质排泄量和排泄物中氨基酸含量的变化规律。以期为确立测定氨基酸生物学效价的方案提供科学依据。结果指出:①喂给不同半纯合日粮时,荷术猪回肠末端干物质排泄量的变异系数(C.V％)随日粮干物质表观消化率(ADDM)的增加而增加;②从喂给不同日粮的荷术猪回肠末端干物质排泄量的变化规律看,如以每3头试验猪统计,预饲3天后,收集4天排泄物可保证排泄量测值的准确性;③排泄物样品中氨基酸含量的稳定性并不因半纯合日粮饲喂期的延长而改善,因此测定氨基酸表观消化率时,可以根据干物质排泄量的稳定性来确定适宜的排泄物收集期。     

大米粉的猪回肠氨基酸真消化率测定

大米加工副产品大米粉长期以来被添加到米糠中利用，显著降低了其利用率。本试验用三头施以回直肠吻合术猪，采用单因子设计，以大米粉为半纯合日粮，无氮日粮由醋酸纤维素提供粗纤维来测定内源值，测定了大米粉的猪回肠末端氨基酸表观消化率和真消化率。大米粉的回肠末端氨基酸的表观消化率的平均值为76．20％，真消化率的平均值为85.86％。这些数据可为我国氨基酸消化率数据库提供参考，并且可作为以可消化氨基酸为基础配制日粮时的依据。     

产蛋鸡内源氮排泄变化规律的研究

选５０周龄罗曼蛋鸡５只，用强饲法供给无氮日粮５３克／千克Ｗ０．７５·天。收集９天的排泄物。结果表明，试验的前３天每日排泄内源氮极显著地高于后６天的日排出量（Ｐ＜０．０１）。而后６天每日的排出量趋于稳定（Ｐ＞０．０５）。测得产蛋鸡内源氮的排泄量为１３３．０毫克／千克Ｗ０．７５·天     

样本含量对真氨基酸代谢率测值的影响

为寻求足以客观反应各种氨基酸生物学效价测值的最小样本含量,作者研究了喂饲蛋鸡日粮、肉鸡日粮、鱼粉日粮、菜籽饼日粮、豆粕日粮、玉米日粮和纯合无氮日粮等7组不同类型日粮时,试验鸡干物质排泄量、干物质表观代谢率和内源性氨基酸排泄量的个体测值变异规律,同时也研究了达到不同测试精度时,相应地所需要的试验鸡群数量。结果表明:(1)饲喂全价日粮和半纯合日粮时,试验鸡个体间干物质排泄量标准差为1.2～2.3g,变异系数为10.5％～17.4％;干物质表观代谢率标准差为2.8％～5.2％,变异系数为3.8％～12.6％。它表明饲喂不同日粮时,试验鸡个体间干物质排泄量和干物质表观代谢率测值差异程度不同。为了保证对各种日粮的干物质表观代谢率测值偏差小于3％和2％(置信度为95％)时,试验鸡数分别需要12只和27只。(2)饲喂纯合无氮日粮时,试验鸡个体间干物质排泄量及干物质表观谢率测值差异则更大。如从内源氨基酸排泄量测值分析,试验鸡个体间各种氨基酸排泄量变异系数都大于20％,因此,即使试验允许偏差值放宽到10％,仍需要40只左右的试验鸡群。     

无氮日粮和酷蛋白对猪回肠内源氨基酸排出量的影响

采用平均体重为65±1.85kg的瘘管猪6头，研究酪蛋白日粮和无氮日粮对猪回肠内源氨基酸排出量的影响。试验结果表明，酪蛋白组中，除Met、Phe、Pro外，几乎所有的内源氨基酸排出量均高于无氮日粮组。其中，His、Ile、Lys、Thr、Val、Asp、Glu、Gly、Ser差异显著(P<0.05)。酪蛋白组的内源氮排出量、内源总必需氨基酸、总非必需氨基酸和总氨基酸的排出量均显著高于无氮日粮组(P<0.05)，提高的百分比分别为941％、730％、764％和748％。由本次试验结果可以得出，无氮日粮法低估了猪的回肠内源氨基酸损失，而在无氮日粮中添加肽类物质（本试验中添加量为5％）对内源氨基酸的排出有刺激作用。     

无氮日粮和酪蛋白对猪回肠内源氨基酸排出量的影响

采用平均体重为 65± 1.85 kg的瘘管猪 6头，研究酪蛋白日粮和无氮日粮对猪回肠内源氨基酸排出量的影响。试验结果表明，酪蛋白组中，除 Met、 Phe、 Pro外，几乎所有的内源氨基酸排出量均高于无氮日粮组。其中， His、 Ile、 Lys、 Thr、 Val、 Asp、 Glu、 Gly、 Ser差异显著 (P< 0.05)。酪蛋白组的内源氮排出量、内源总必需氨基酸、总非必需氨基酸和总氨基酸的排出量均显著高于无氮日粮组 (P< 0.05)，提高的百分比分别为 94.1％、 73.0％、 76.4％和 74.8％。由本次试验结果可以得出，无氮日粮法低估了猪的回肠内源氨基酸损失，而在无氮日粮中添加肽类物质（本试验中添加量为 5％）对内源氨基酸的排出有刺激作用。     

无氮日粮法和酶解酪蛋白超滤法测定肉仔鸡内源氨基酸损失量的比较研究

选用40日龄平均体重(2500±50)g商品代AA肉公鸡120只,随机分为无氮日粮组和酶解酪蛋白组,分别饲喂无氮日粮和含酶解酪蛋白的日粮,36h后取回肠末端食糜,测定回肠末端内源氨基酸流量。结果表明:酶解酪蛋白超滤法测定的17种氨基酸的回肠末端内源流量,都高于无氮日粮法的测值,其中12种氨基酸(除甘氨酸、半胱氨酸、酪氨酸、苯丙氨酸和组氨酸)的差异显著(P<0.05);17种氨基酸总的内源流量,超滤法比无氮日粮法高22.7%(P<0.05)。     

泡桐叶用作单胃动物饲料的营养价值评定

泡桐是一种多年生落叶乔木，具有抗干旱、耐盐碱的特点，在我国“三北”地区分布很广，是一种很有前途的速生树种。为综合利用泡桐资源，探讨确立泡桐叶作为单胃动物粗饲料的营养价值，本文在测定热喷及未热喷泡桐落叶的概略养分、钙、磷、氨基酸含量的基础上，分别采用Ｓｉｂｂａｌｄ（１９７７）“ＴＭＥ”改良法、猪小肠液体外消化试验法和回─直肠吻合荷术猪方法，研究了泡桐落叶的干物质、粗蛋白质、能量的消化率（猪）和代谢率（鸡）。结果指出：①热喷与未热喷泡桐叶干物质中粗蛋白、粗纤维、无氮浸出物、粗灰分、总能等概略养分及钙、磷、各种氨基酸含量基本相同，但热喷泡桐叶较未热喷泡桐叶中粗脂肪含量略低。表明虽然热喷处理可引起部分脂肪的挥发损失，但热喷处理对其他各种养分的化学成分含量影响很小，未热喷泡桐叶干物质中含粗蛋白质１１．４６％、粗纤维１８．１０％、粗脂肪３．４８％、粗灰分１７．９６％、总能４１７２．５千卡／千克、钙２．７５％、磷０．１４％、总必需氨基酸４．１４％、总氨基酸８．７２％；热喷泡桐叶干物质中含粗蛋白质１１．７１％、粗纤维１８．２７％、无氮浸出物４８．３０％、粗脂肪３．０８％、粗灰分１８．６４％、总能４０７９．７千卡／千克、钙２?     

肉仔鸡内源氨基酸基本损失量测定方法的比较研究

通过强饲无氮饲粮(NFD)、NFD +3.39 %平衡氨基酸(AAs)、NFD +6.81 %AAs、NFD +3.20 %酶解酪蛋白(EHC)或NFD +6.40 %EHC饲粮 ,直接测定肉仔鸡48h内源氨基酸基本损失量(EAAEb)。给肉仔鸡强饲以豆粕为唯一氮源的粗蛋白(CP)含量为5 %、10 %、20 %及30 %饲粮 ,利用回归法(REG)间接研究EAAEb。结果表明 ,上述几种方法测定的EAAEb 相似 ,说明肉仔鸡有一相对稳定的EAAEb。     

贵州南部苇状羊茅混播草地营养成份含量动态测定

对在贵州南部地区生态条件下表现优良的草种组合 :苇状羊茅 +扁穗雀麦 +白三叶人工草地各种牧草的各个生育阶段及草地全年各月份营养成份含量进行了测定。结果表明 :四种混播牧草的粗蛋白、粗脂肪和灰分三种营养成份含量都是随着生育期的推后呈线性下降 (P <0 0 1) ,酸性洗涤纤维含量随着生育期的推后呈线性上升 (P <0 0 1) ,无氮浸出物的含量变化跟生育期无明显联系 ;混播草地全年各月份营养成份含量变化规律为 :粗蛋白、粗脂肪及灰分在 1～ 7月份较高 ,8、9、10月份最低 ,11、12月份又逐步回升 ,粗蛋白含量尤以 4、5、6月份含量最高。酸性洗涤纤维的含量变化跟粗蛋白等情况相反 ,无氮浸出物含量各月间无显著变化。     

Effects of different feeding and housing conditions on dry matter content and consistency of faeces in sows

In a study with sows at various stages of the reproductive cycle, the effects of parturition, feed quantity and composition (content and type of crude fibre), exercise and access to water on dry matter content, and consistency of faeces were estimated. Parturition caused an increase in the dry matter content and reduced the defaecation frequency. The restriction of feed amounts in the last days of gestation and the change to lactation feed with reduced crude fibre content (6-3% in feed) intensified the physiologically occurring increase of the dry matter content. Moving activity and the amount of water ingested had only a small insignificant effect on the moisture of the faeces. The faeces became markedly softer when large amounts of fermentable fibre were used in the diet. The risk for constipation in periparturient sows increases when feed amounts and fibre content in the diet are strongly reduced. Therefore, it is recommended to offer sows daily minimum amounts of a diet (<2 kg) containing >7-8% crude fibre (including a highly fermentable fibre to improve faeces consistency) especially on the days near parturition.     

The nutritive value of mulberry leaves (<Emphasis Type="Italic">Morus alba</Emphasis>) as a feed supplement for sheep

A study to determine the nutritive value of mulberry (Morus alba) leaves in sheep diets was conducted. Mulberry leaves contained (g kg⁻¹ on dry matter basis): 163 ash, 201 crude protein, 120 crude fibre, 37 ether extracts, 479 nitrogen-free extracts, 268 neutral detergent fibre, 148 acid detergent fibre, 41 acid detergent lignin, 121 cellulose and 107 hemicellulose, while the in vitro true digestibility of dry matter was 89.8%. The nitrogen (N) solubility, determined using: a) McDougall’s buffer, b) 0.02 N sodium hydroxide (NaOH) and c) 0.15 N sodium chloride (NaCl) as solvents, ranged from 11.6 to 14.9% of total N. In addition, the soluble non-protein nitrogen contributed a substantial part of total N (26.1%), the total true protein was 14.4% and the protein fractions evaluated after classical protein fractionation, were: albumins 11.1, globulins 9.7, prolamins 44.1, glutelins 8.5 and insoluble (or structural) proteins 26.6% of total N. In a digestibility trial, where mulberry leaves partially replaced lucerne hay and concentrates in wether sheep diets, there were no significant differences in dry matter, crude protein or crude fibre digestibility of the total diet. It was concluded that mulberry leaves have an appreciable potential as a protein source in sheep feeding.     

Digestibility of nutrients in a feed mixture in certain swine helminthiases

The average digestibility coefficients of feed mixture nutrients in pigs infected medium severely to severely by the helminths Ascaris suum and Oesophagostomum dentatum were lower in comparison with the post-dehelminthization condition (dry matter by 3.1%, crude protein by 6.7%, fat by 8.9%, nitrogen-free extracts and fibre by 2.2%, organic matter by 3.1%). The content of total digestible nutrients made 679 g in infected pigs and 708 g in dehelminthized pigs. In the period following the experimental infection of pigs by the helminths Ascaris suum, characterized by the formation of antibodies and adaptation after heavy injury of the organism, the digestibility coefficients of feed mixture nutrients were in comparison with the state prior to infection influenced positively. In two metabolism trials, on the 9th to 13th day after infection the digestibility coefficients increased as follows: of dry matter by 4.8% and 3.6%, crude protein by 8.2 and 4.2%, nitrogen-free extracts and fibre by 2.0 and 3.5% and organic matter by 3.0 and 3.3%. The decrease in fat digestibility coefficients was observed in both cases, by 12.4% and 9.9%. Prior to infection the content of total digestible nutrients was 712 g and 682 g, after infection 731 g and 707 g.     

无氮日粮纤维类型及进食量对猪内源氨基酸测值的影响

分别以醋酸纤维素与微晶纤维素为纤维源配制成粗纤维水平为５％的两种无氮日粮。其中微晶纤维日粮设高进食量（１０００ｇ／ｄ）与低进食量（５００ｇ／ｄ）两个处理,醋酸纤维日粮只设一个进食量（１０００ｇ／ｄ）处理,共三个处理,以３＊３拉丁方式验研究纤维来源及进食量对回－直肠吻合猪消化道内源氨基酸排泄的影响。     

Studies in male sheep on the feeding value of excreta from young hens and broilers]

5 digestibility trials were carried out, each with 4 male sheep, to investigate the excreta of young hens and broilers produced as litter in hen batteries for rearing and fattening stock. Data on the digestibility of organic matter and energy of broiler excreta were 76.0% and 76.4%; i.e. these values were only slightly lower than those for the basal ration (barley + dried green lucerne: 76.6% and 76.8%). Digestibility coefficients for organic matter and energy content in the excreta of young hens were 69.4% and 70.4%, respectively. The protein digestibility of excreta of broilers and young hens was 82.3% and 84.3%; that is to say, the investigated dropping contained 330 g and 260 g of digestible crude protein per kg of dry matter. Due to the high ash content of the samples the energy content of the analyzed excreta was only 474 EFr and 421 EFr per kg of dry matter.     

Effect of a supplement of partly hydrolized straw meal to a diet of fish meal and horse beans on N balance and amino acid excretion in the feces of swine

2 test pigs each (male castrated pigs) of an average live weight of 51-71 kg received either a wheat/fish meal diet (Ia) or a wheat/horse bean diet (IIa). Due to a supplement of partly hydrolysed straw meal the crude fibre content was increased from 3.0% (= Ia) to 10.1% (= Ib) and from 5.2% (= IIa) to 12.1% (= IIb) in the dry matter. This straw meal supplement decreased the apparent digestibility of the crude protein in I from 92.5 to 85.7% and in II from 89.0 to 79.0%. N-excretion in faeces/100 g DM-intake followed the regression line: y = 228 + 31.2x(r = 0.98) y = mg N/100 g DM-intake x = % crude fibre in the DM of the diet The excretion in faeces/100 g DM-intake of 15 investigated amino acids, too, in each case showed a significant increase with the rising crude fibre content of the diet. The widest growth angle (tan alpha) of all the essential amino acids investigated was shown by lysine and those amino acids with branched chains. The conclusion is that in the presence of a fermentable crude fibre source and a good N-supply those 4 amino acids show a suitable bacterial synthesis rate and a low decomposition rate.     

肽对肉鸡生长性能的影响及其生理机理研究

将1日龄爱维因公肉仔鸡150只,随机分为3处理,每处理5重复,每重复10只鸡,3处理肉鸡分别采食按IICP(1994)理想蛋白模式配制的肽、酪蛋白和游离氨基酸日粮,试验期3周。结果表明:肽组和酪蛋白组肉鸡分别比氨基酸组增重提高44.14%和37.35%,酪蛋白组料肉比分别比肽组和氨基酸组降低12.484%和11.294%。肽组和酪蛋白组肉鸡体内干物质含量分别比氨基酸组提高9.88%和10.32%(P<0.05);干物质中氮含量,肽组和酪蛋白组肉鸡分别显著(P<0.05)或极显著(P<0.01)低于氨基酸组;干物质中脂肪含量,肽组和酪蛋白组极显著高于氨基酸组(P<0.01)。肽组日粮氮和能量沉积率分别比氨基酸组高5.22%和11.40%,酪蛋白组日粮氮和能量沉积率比肽组高7.19%和19.91%,酪蛋白组血清胆固醇和甘油三酯含量分别比肽组高17.82%和28.21%,比氨基酸组高13.78%和73.88%,肽组甘油三酯含量比氨基酸组高35.62%。酪蛋白组肉鸡血清中高、低密度脂蛋白显著(P<0.01)大于肽组和氨基酸组,肽组和氨基酸组血清尿酸含量显著(P<0.05)大于酪蛋白组。酪蛋白组的丙氨酸转氨酶活性极显著大于氨基酸组(P<0.01);肽组和酪蛋白组肉鸡生长激素含量显著(P<0.05)或极显著(P<0.01)大于氨基酸组。